Effect of Non-Chemical Weed Management Approaches on Yield and Nutrient Uptake in High Density Planting of Cotton in Vertisol of Northern Karnataka

In order to investigate the impact of non-chemical eco-friendly weed management strategies on the yield, nutrient uptake, and soil balance of high density planting cotton in deep vertisols, a field experiment was carried out in 2017 and 2018 at the Department of Agronomy, College of Agriculture, UAS, Raichur. Three replications were used in the experiment's Randomized Completely Block Design layout. There were 14 different interventions used, including polythene mulch, paddy straw mulch, cotton stalk mulch, intercropping with green manures at a 1:1 ratio (sunnhemp and cowpea), four different botanical extracts at 20% as PE (Eucalyptus sp., Prosopis juliflora extract, Cassia tora, and Parthenium hysterophorus), mechanical, cultural, and their combination, in comparison to weed-free check. Three replicated randomised complete block design was used to conduct the experiment. The two years pooled data showed that, compared to the other treatments, weed free check had a significantly higher seed cotton production (1,722 kg /ha). It was then followed by Cotton + Sunnhemp (1:1) in-situ mulching at 45 DAS (1299 kg /ha), pendimethalin 38.7 CS @ 680 g a.i./ha as PE fb pyrithiobac sodium 10 EC 75 g a.i./ha + quizolofop ethyl 37.5 g a.i./ha at 25 DAS as PoE (1274 kg /ha), The environmentally friendly treatments, such as cotton + sunnhemp (1:1) and in-situ mulching at 45 DAS, mulching with black polythene sheet, cotton + cowpea (1:1) and in-situ mulching at 45 DAS, and others, were on par with weed free check and may be suggested since they were the best options.